There are three different types of inverters:
- Square Wave Inverter
- Modified Sine Wave Inverter
- Pure Sine Wave Inverter
What Is A Square Wave Inverter?
As the name suggests, square wave inverters create a “square” wave. The inverter creates a “wave” that instantly flips between positive and negative voltages rather than more gradually.
It pauses at the AC voltage level (110v or 240v) before flipping to the opposite polarity.
The component parts are simple, so square inverters are low-cost.
This waveform is far removed from that of the mains supply, which is a pure sine wave.
Typically, square wave inverters are ok for running lights and mechanical fans. Sensitive electronics can be irreparably damaged if connected to one of these, though.
The applications for square wave inverters are so limited, there are few, if any, models available on the market today.
What Is A Modified Sine Wave Inverter?
A modified sine wave inverter produces a stepped wave.
Rather than instantly flipping between the positive and negative voltage, it produces a smoother waveform, though still a little clunky.
Following the general shape of a pure sine waveform, the voltage increases in increments with tiny pauses in between until it reaches the AC voltage level.
The power inverter then reduces the voltage in similar incremental steps until it reaches the opposite polarity.
Modified sine wave inverters are more expensive, with component parts more complex than a square wave model, but they are widely available.
Update: square wave inverters are almost impossible to buy now, so modified sine wave inverters are the cheapest available in today’s market.
A modified sine wave inverter can run simple appliances without sensitive electronics.
Water pumps, camera batteries, and laptop chargers will probably run fine, but other appliances like LED TVs or digital clocks won’t work.
What Is A Pure Sine Wave Inverter?
A pure sine wave inverter produces power that most closely matches a mains supply.
The voltages it produces increase and decrease in a smooth transition from positive to negative.
The waveform is smooth, giving a clean, consistent supply of energy.
A pure sine wave inverter will run all your electrical appliances and campervan gadgets.
Though a pure sine wave inverter is more expensive than a modified sine wave, it won’t damage your sensitive electronics. In the last few years, the price of pure sine wave inverters has fallen, shrinking the price difference.
Because they’re becoming more affordable and are more versatile than a modified sine wave, we recommend pure sine wave inverters for RV campers.